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// SPDX-License-Identifier: GPL-2.0
/*
* Re-map IO memory to kernel address space so that we can access it.
* This is needed for high PCI addresses that aren't mapped in the
* 640k-1MB IO memory area on PC's
*
* (C) Copyright 1995 1996 Linus Torvalds
*/
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/io.h>
#include <linux/export.h>
#include <asm/cacheflush.h>
#include "pgalloc-track.h"
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
static unsigned int __ro_after_init iomap_max_page_shift = BITS_PER_LONG - 1;
static int __init set_nohugeiomap(char *str)
{
iomap_max_page_shift = PAGE_SHIFT;
return 0;
}
early_param("nohugeiomap", set_nohugeiomap);
#else /* CONFIG_HAVE_ARCH_HUGE_VMAP */
static const unsigned int iomap_max_page_shift = PAGE_SHIFT;
#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
int ioremap_page_range(unsigned long addr,
unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
return vmap_range(addr, end, phys_addr, prot, iomap_max_page_shift);
}
#ifdef CONFIG_GENERIC_IOREMAP
void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
{
unsigned long offset, vaddr;
phys_addr_t last_addr;
struct vm_struct *area;
/* Disallow wrap-around or zero size */
last_addr = addr + size - 1;
if (!size || last_addr < addr)
return NULL;
/* Page-align mappings */
offset = addr & (~PAGE_MASK);
addr -= offset;
size = PAGE_ALIGN(size + offset);
area = get_vm_area_caller(size, VM_IOREMAP,
__builtin_return_address(0));
if (!area)
return NULL;
vaddr = (unsigned long)area->addr;
if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) {
free_vm_area(area);
return NULL;
}
return (void __iomem *)(vaddr + offset);
}
EXPORT_SYMBOL(ioremap_prot);
void iounmap(volatile void __iomem *addr)
{
vunmap((void *)((unsigned long)addr & PAGE_MASK));
}
EXPORT_SYMBOL(iounmap);
#endif /* CONFIG_GENERIC_IOREMAP */